South Korea's Red Cross said Wednesday its programs for families separated by the 1950-53 Korean War and humanitarian aid to North Korea now face a murky prospect as North Korea's fourth nuclear test froze ties between the two countries.

The Red Cross has made video messages of about 10,000 separated family members to be possibly delivered to their relatives in North Korea, but whether they can be delivered remains uncertain due to the strained inter-Korean ties following the North's nuclear test on Jan. 6, it said.

Seoul has also proposed to Pyongyang that the two Koreas exchange a list of how many separated family members from each side want to meet with their relatives living across the border. There are about 66,000 separated family members in South Korea, half of which have expressed a wish to confirm the fate of their relatives living in the North.

"(Due to the North's nuclear test), there has been no progress over our projects on separated families and humanitarian assistance with North Korea," a Red Cross official said.

The two Koreas arranged brief reunions of families split by the war, which ended in a truce, not a peace treaty, at a facility on Mount Kumgang in the North in late October. The event, the first since early 2014, involved fewer than 100 families from each side.

The two sides have held 20 rounds of such reunions so far, but tens of thousands of more people are still on the waiting list.

South Korea is seeking to hold the family reunions on a regular basis, calling on the North to allow such families to exchange letters. But Pyongyang maintains a lukewarm stance. (Yonhap)